Correctional Services spokesman Manelisi Wolela has denied allegations that student leader Mcebo Dla.
A 25-year-old Malawian man suffered serious head injuries when he was allegedly knocked down by a minibus taxi.
The accident happened in Fourways, Johannesburg, yesterday.
ER24 spokesman Werner Vermaak said: "According to friends of the pedestrian, they were waiting next to the road to cross at about 6am when he [the patient] was knocked down by a taxi."
The man, with major head and pelvic injuries, was stabilised at the scene, but had to be airlifted from the Fourways Life Hospital to the Johannesburg General Hospital.
"At this stage it is unknown who was at fault at the time of the accident," Vermaak said.
The taxi was apparently on its way to Zevenfontein informal settlement. The driver was not injured.
The pedestrian was found several metres from the side of the road. - Sapa